The present invention relates to reverberatory heating furnaces for melting metals, and more particularly to aluminum melting furnaces in which heat may be generated by alternate energy sources.
It has long been known to use fossil fuels, such as natural gas, oil, propane, and methane, in operating reverberatory furnaces; more recently, it is known to use electrical resistance heating elements in such furnaces. While the use of either fossil fuels or electricity in metal melting furnaces is generally considered to be dependable, economical and efficient, the ready availability of fossil fuels and electricity to industrial users is no longer presumed as it was in the past. Rather, the fossil fuel or electricity consumer is often threatened with shortages, seasonal and otherwise, with fossil fuels scarce during some periods and electricity scarce in other periods. The operator of a metal melting furnace in the predicament of a shortage of his normal source of energy may have to curtail or even cease operation of the furnace. The alternative of having duplicate furnaces, one using fossil fuel and the other using electricity, is manifestly impractical.